Continuity mistake: At the start of the episode, when the first victim is found, she is unidentified. However, before Garcia finds out the victim's name is Sarah Rhodes, we already see a label with the name Sarah Rhodes written on it. (00:07:03)
Revealing mistake: When Morgan is typing "Cult named Forever People," his phone is typing it automatically. His fingers aren't even tapping the correct letters. (00:19:45)






Chosen answer: Black SUVs are common police, military and dignitary vehicles around the world. It is not too much to assume they could be rented or owned by the police forces in the areas.
kristenlouise3
Other people have explained it but fore more information, federal cars would most likely be brought to the airport from the nearest agency, so they can drive out to their locations especially in rural situations.